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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 出1-21之间不能被2整除的累加和
        var sum = 0;
        for (var i = 1; i <= 21; i++) {
            if (i % 2 !== 0) {
                sum += i;
            }
        }
        console.log(sum);

    </script>
</body>
</html>